Motor



Aug. 19, 1941. K. K. PROBST MOTOR Filed Jan. 20, 1939 INVENTOR- @obs/ ATTORNEY? Patented Aug. 19 1941 MOTOR Karl K. Pi'obst, Detroit, Mich, assignor, by mesne assignments, to W burg, Pa., as trustee illiam L. Hoburg, Sha ps- Application January 20, 1939, Serial No. 251,939

6 Claims.

This invention relates to a motor embodying a wobble plate actuated by fluid pressure and has for its primary object to provide the wobble plate with fluid pressure sealing means enabling eflicient operation with air under pressure as the actuating medium.

A conventional wobble plate motor comprises a plate or. disc mounted centrally upon a sphere which is seated in a spherical bearing formed at the convergence of two opposed conical end walls oi 'an enclosing chamber having a spherical side wall; A radial partition extends from the supporting sphere to the spherical side wall and sible dimensional variances. The result is that with all dimensions held to comparatively small limits the accumulation of tolerances almost invariably results in loss of efliciency due to ime proper correlation of the wobble plate and the conical end walls. Tests indicate that the average efliciency of production mo't'ors actuated by air under pressure is about 10%, although" the fluid pressure intake and exhaust ports are provided on opposite sides of the partition. When a fluid under pressure is circulated through the 1 chamber, from the intake around the partition to the exhaust, it causes the plate or disc to gyrate or rock circularly, with a tilting or wobbling motion.

' It is readily apparent that the emciency of this type of motor is mainly dependent upon sealing the wobble plate by a means which does not mtroduce excessive friction. For example, it fluid passes between the periphery of the disc and the spherical side wall. a power loss occurs. Further, when one side of the wobble plate contacts one conical end wall. the other side must contact the other conical end wall, with both contacts onthe same diametric line. If one side fails to contact. even by a few thousandths 0! an inch, the wobble plate will stall unless the actuating fluid is of viscous character.

The fluid loss between the periphery of the wobble plate and the spherical side wall or the respect to the conical end walls with which they coact.

The motor chamber, in order to facilitate assembly oi' the wobble plate, must be formed in at least two sections, which introduces a multiple factor of error in that the conical end walls must the wobble plate, its supporting sphere, the bearings at the convergence of the conical walls, and

assembly of the wobble plate all introduce possame motors have higher efflciency when operated "by liquids under pressure,- particularly liquids of viscous nature such as oil.

Accordingly, it is the object of this invention to provide means for sealing the wobble plate in the presenceof dimensional discrepancies, which ordinarily would result in loss of power. More specifically, the object is to interpose sealing means in the form of a layer of soft, resilient material, such as rubber, between the sides of the wobble plate and the conical end walls with which they coact.

A further object is to provide a wobble'plat motor embodying sealing means enabling efiicient operation with the exhaust connected to a source ofsuction and the intake connected to the atmosphere, with the air at atmospheric'pressure providing the means for actuating the motor. The motor is, therefore, adapted for operating the windshield wiper of an automotive vehicle.

Other objects and advantages will become more apparent as reference is had to the accompanying drawing wherein my invention is illustrated, and in which: i

Fig. 1 is an end elevation with the gear housing removed; I

Fig. 2 is a section taken on the line 2-2 of Fig. 3, with disc and fittings shown in elevation;

Fig; 3 is a section taken on the line 3-4 of F18.

Fig. 4 is a section of a modified wobble plate;

Fig. 5 is a section of a resiliently flexible wobble plate,- and I I Fig. 6 is a section illustrating sealing means of varied resiliency.

The motor housing is formed of two sections i and 2 having complemental internal surfaces 3 and 4, respectively, which constitute a spherical side-wall oi the motor chamber. The sections i and 2 have inwardly converging conical walls 5 v and 8 which constitute the end walls oi the motor chamber, the conical walls being truncated and having spherical bearings I and 8 in metric relation thereto. The plate II has a recess ll accommodating a radial partition I! on opposite sides of which are provided a fluid inlet [3 and a fluid outlet I. A pin II, loosely and the adJacent conical walls. To prevent such leakage of fluid the conical walls 5 and 6 have pads of soft, resilient material I and I1 secured thereon, an example of such material being soft rubber, or sponge rubber. As the plate ll is gyrated it has a line contact with the pad I. on one side thereof and with the pad I1 and inasmuch as both pads are capable of being compressed the several parts oi the pump may be proportioned to cause the plate to compress the same on the lines of contact. The pads l6 and I! also contact the sphere 9 and prevent leakage of fluid through the bearing 1 and 8.

In the case of a windshield wiper motor, the port I3 is connected to the atmosphere and the port I is connected to a source of suction such as the intake manifold. The average pressure under such conditions, considering variations in throttle position, amounts to about flve pounds per square inch. In such a case the pressure which tends to hold the plate against the rubber amounts to say ten pounds, and the rubber should be sufliciently soft to compress about .006 of an inch on the line of contact in the presence of ten pounds pressure.

As the plate "I gyrates the outer end of a stem i8 secured to the sphere 9 is moved through a circular orbit, and thereby imparts rotation to a disc I! which it engages. Through gears 20, 2|, 22 and 23 rotation is imparted to the final shaft 24 which carries the arm 25. The arm 2'! may be connected through suitable linkage to a device to be operated, which might readily be imagined as comprising a windshield wiper.

Mounting rubber pads on the conical walls is desirable from the standpoint of manufacture and assembly, but it is readily apparent that the function would be substantially similar in a case where the elastic pads are secured to the wobbler plate. In Fig. 4, rubber pads I64: and I 1a are shown mounted on the wobble plate la. From Fig. it also become apparent that the wobbler plate might be made entirely of yieldable material. In this case the plate lflb is composed of material having the characteristics of rubber, but with suflicient rigidity to withstand collapse under the pressures to which it it to be subjected.

It is apparent that if the wobble plate In and sphere 9 is moved rotatively about an axis coinciding'with the center of the sphere 9 and perpendicular to the sheet as Fig. 3 is viewed by the reader, the peripheral edge of the plate travels a greater distance than a point adjacent the sphere for a movement through a given number of degrees. Therefore, the edge of the seals I6 and I1 adiacent the spherical surface 3 must be deflected to a greater extent than the edge adjacent the sphere. To accommodate this condition,'the elastic pad lib may be grooved as illustrated in Fig. 6, the grooves being arranged to provide greater yieldability adjacent the outer edge than the inner edge.

Although specific embodiments of the invention have been illustrated and described, it will be understood that changes may bemade within the scope of the appended claims without departing from the spirit of the invention, and such changes are contemplated. I

What is claimed is:

1. In a motor having inwardly converging conical end walls, a spherical side wall, a radial partition and inlet and outlet ports on opposite sides of the partition, a wobble plate mounted at the convergence of said conical walls, and elastic sealing pads interposed between said wobble plate and conical walls and in direct contact with said wobble plate, said wobble plate having a thickness such that it normally distorts the elastic pads at the lines of contact therewith.

2. In a motor having inwardly converging conical end walls, a spherical side wall, a radial partition and inlet and outlet ports on opposite sides of the partition, a wobble plate mounted at the convergence of said conical walls, and pads of soft rubber on said conical walls for direct contact by said wobble plate and normally deformed thereby.

3. In a motor having inwardly converging conical end walls, a spherical side wall, a radial partition and inlet andoutlet ports on opposite sides" of the partition, a wobble plate mounted at the convergence of said conical walls, and elastic sealing pads interposed between said wobble plate and conical walls, said sealing pads being of greater elasticity at their outer edges than at their inner edges.

4. A motor having an air inlet port open to the atmosphere and an outlet port adapted to be connected to a source of suction, said motor having inwardly converging conicalend walls; a spherical side wall, a radial partition, said inlet port being disposed on one side .of said partition and said outlet port being disposed on the other side, a wobble late mounted at the convergence of said conical walls, and sealing pads interposed between said wobble plate and conical walls, said sealing pads being of a thickness such that they are normally compressed approximately .008 in., and having resilient qualities such that in the presence of such compression the reaction pressure thereof does not exceed approximately ten pounds.

5. A motor having an air inlet port open to the atmosphere and an outlet port adapted to be connected to a source of suction, said motor having inwardly converging conical end walls, a spherical side wall, a radial partition, said inlet port being disposed on one side of said partition and said outlet port being disposed on the other side, a wobble plate mounted at the convergence of said conical walls, and sealing pads interposed between said wobble plates and conical walls, said pads comprising preformed conical members and being secured to said conical walls, said sealing pads being of a thickness such that they are normally compressed approximately .006 in., and

having resilient qualities such that in the presence of such compression the reaction pressure thereof does not exceed approximately ten pounds.

6. A motor having an air inlet port open to the atmosphere and an outlet port adapted to be connected to a source of suction, said motor having inwardly converging conical end walls, a spherical side wall, a radial partitiomsaid inlet port being disposed on one side of said partition mally compressed approximately .006 in., and having resilient qualities such that in the presence of such compression the reaction pressure thereof does not exceed approximately ten 5 pounds.

KARL K. PROBST. 

